The present invention relates to a graft with a stent such as an artificial blood vessel with a stent, and to a graft with a thin stent which is free from transudabon of blood at the connection with a blood vessel and hindrance of blood from flowing by kink and/or arctation.
At present, a tubular film with a stent is mainly used for an endovascular surgery of aneurysm or the like. When a blood vessel is narrow, celiotomy is required to insert a sheath in a blood vessel from a thick portion thereof. Thus, a total percutaneous intravascular surgery is sometimes difficult.
Since a tubular film with a stent on the inner surface of the tubular film is most popular, various kinds of materials forming the stent, such as metals, plastics or the like, directly contact organism and/or blood, which sometimes causes a problem.
In the aforementioned tubular film with a stent, the stent is sometimes fixed on the inner or outer surface of the tubular film by the use of an anastomotic thread and a needle. In this case, the tubular film is occasionally holed partially by the needle, which causes transudation of blood.
As an example in which a stent is fixed on a tubular film or in which a in which a coating layer comprising a tetrafluoroethylene resin porous film is disposed on the inner and outer surfaces of a tubular structure composed of an elastic wire rod.
JP-A-8-141090 discloses an indwelling type stent, which comprises a stent body being formed so as to have an almost tubular shape, having a plurality of openings passing from the outer surface to the inner surface of the tubular shape, and being shrinkable in the diametral direction; a thermoplastic resin layer covering the stent, and a tubular cover covering the outer and/or inner periphery of the stent body, closing up the openings, and fixed to the thermoplastic resin layer. Since, the stent body is covered by a thermoplastic resin layer; the stent does not directly contact an organism. However, it is may be possible that the stent cannot move flexibly in accordance with a movement of organism when it is indwelt, for example, a movement such as expansion and contraction in a longitudinal or diametral direction because the stent is completely fixed to the tubular cover.
JP-A-9-173468 discloses a covered stent being provided with, inside a stent support, a coating layer being substantially free from the pores which allow cells to pass therethrough and, outside thereof, a coating layer in which fibers are entangled each other irregularly, and a method for producing the same.
The present invention is intended to provide a graft with a thin stent and a method for producing the same. The stent does not directly contact an organism and is capable of being indwelt in an organism. The graft is free from hindrance of blood from flowing by kink and/or arctation in a corner such as an arched portion, a curved portion, and meandering portion; is resistant to expansion and contraction and bending; is fit for a shape of a blood vessel of a human body; and is usable for a total percutaneous intravascular surgery.
According to the present invention, there is provided a graft with a stent, comprising:
a stent composed of a resilient wire forming a zigzag shaped supporting frame made of a wire; said zigzag shaped supporting frame having top and bottom portions; and
tubes each being made of plain woven of polyester resin fibers and each having a thickness of 20 xcexcm to 100 xcexcm;
the tubes being disposed respectively on the inner surface and the outer surface of the stent, and the inner surface of the outer tube and the outer surface of the inner tube being partially adhered to each other by a polyester resin.
It is preferable that the. inner surface of the outer tube and the outer surface of the inner tube are adhered to each other by injecting a polyester resin from the side of the outer surface of the outer tube.
Specifically, the zigzag shape of the stent terminates in end portions. The stent is disposed between the inner tube and the outer tube, the stent, inner tube, and outer tube being concentrically arranged. The outer surface of the inner tube and the inner surface of the outer tube are adhered to each other by a polyester resin only at spaced discrete points within the boundaries of the stent.
It is more preferable that the inner surface of the outer tube and the outer surface of the inner tube are partially adhered to each other at the top and/or the bottom portions of the stent